High speed injecting molding method by counter pressure method and chemical foaming method

Abstract

The invention involves a counter-pressure chemical foaming high speed injection moulding shaping method. The invention provides a method which utilizes injection moulding shaping machine equipment, and dies, general gas energy, plastic raw materials and other system resources comprehensively, produces thick-wall plastic-foam product high speed and high effectively. The invention first closes the die and injects gas into die cavity, then injects molten material into die cavity, the welding fluid is full of die cavity after inner foaming, the molten material surface is closed to the metal wall-surface of die cavity, the molten material in die cavity is solidified and shaped after cooled, then opens the moving mold and static mold, the plastic products are prepared which surface is smooth anddense and inner is distributed with uniform foam. The invention can eliminate or reduce the converging cave and warping deformation of product surface, reduces injection moulding pressure, thereby reduces the lock-mode pressure of injection machine; reduces equipment operating costs, thereby improves the size accuracy and strength of products, can reduces 15% ~ 35% raw material consumption effectively, products have higher mechanical property and weight proportion.

Description

technical field [0001] The invention relates to a chemical foaming injection molding process method for foamed plastic parts, in particular to a low-pressure chemical foaming injection molding process for thick-walled plastic foamed parts used in industries such as auto parts, sports equipment, home appliances and toys. Forming method. Background technique [0002] Affected by factors such as oil prices and material energy shortages, global plastic raw material prices are on the rise, and plastic application technologies that save raw materials and improve efficiency have developed rapidly. In terms of injection molding, foam molding, gas-assisted injection molding and water-assisted injection molding and other application technologies and equipment development are important components of the development of the plastics industry and processing technology in recent years. Foam injection molding technology is one of the most popular technologies in the industry. The most inte...

AI Technical Summary

Problems solved by technology

However, the requirements set in the processing process are relatively high, requiring more complex mechanical device technology, and the established procedures involve a wide range; thus, more resources are required for the processing (or forming) of the parts

On the other hand, some foaming injection molding processes prevailing at home and abroad have certain restrictions on the application of parts; for example, the "MuCell (micro-foaming molding process)" process is not suitable for producing transparent parts due to appearance factors , and because of the rough surface of the workpiece, it cannot be used for secondary decoration processing, such as silk screen printing, pad printing, electroplating, etc.

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